valid checkpoints were added to Maxcoin by now? For reference, Bitcoin developers are adding checkpoints with every few wallet updates.
You're talking over my pay grade, but, I did
maxcoin-qt -reindex
last night using the intermediate fix version (maxcoin-qt-0.9.3) and all is good ever since. The latest maxcoin-qt (-9.3.1) is performing flawlessly so far.
18:16:12

getinfo
18:16:12

{
"version" : 90301,
"protocolversion" : 70005,
"walletversion" : 60000,
"balance" : not enough 8-}
"blocks" : 620753,
"timeoffset" : 0,
"connections" : 4,
"proxy" : "",
"difficulty" : 10319.99134975,
"testnet" : false,
"keypoololdest" : 1391863498,
"keypoolsize" : 104,
"paytxfee" : 0.00000000,
"errors" : ""
}
I do have
enforcecheckpoint=false
at the end of my maxcoin.conf, as recommended.